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File I/O Lab

Work with file I/O in Java.

Introduction

The goal of this lab is to practice working with Java file I/O by adding load/save functionality to the Document class you completed in a previous lab.

The code for this lab was originally designed as a command-line Java application so you may want to run it in the terminal. It is also fine to run it through the Eclipse console.

As a reminder, you can follow the following steps to compile and execute a Java program in a Linux/OSX terminal:

cd the_directory_where_your_code_is_stored
javac File1.java File2.java ...
java File1

This example assumes that File1.java contains the main method for the application.

Resources

Useful API documents:

Files

The following unfinished files are provided:

Instructions - Part 1

Download the files above and complete Document.java so that the unfinished methods conform to the Javadoc comments. Test your completed file by running the provided application program.

Instructions - Part 2

The current implementation of the Editor class does not include code for handling exceptions related to file I/O: If you attempt to open a non-existent file, or to write a file to a location where do not have permission, the application will crash.

Modify Editor.java by removing all throws declarations and adding try/catch blocks to saveFile and loadFile. If an exception occurs, these methods should print a helpful error message and then allow execution to proceed normally.

Instructions - Part 3 (If Time)

Most text editors allow you to save the current document without re-entering the file name. Modify the Editor class so that it provides this functionality. If the file is already associated with a file name (because of an earlier save or load) then the “s” command should now save the current version without prompting for a file name. You should also add a save-as command to allow specifying a file name even if one already exists. Use “w” to trigger save-as. Make sure to update the help message to conform to the new functionality.

Submitting

Submit your completed versions of Document.java and Editor.java to Gradescope . You have an unlimited number of submissions. If you have trouble with your submission, you may find it helpful to look at the JUnit submission tests: